Prevention and control of perinatal hepatitis B virus transmission in ...

Ranger-Rogez S, Alain S, Denis F. Hepatitis viruses: mother-to-child transmission. Pathol Biol(Paris) 2002; 50:568-575. [Article in French]Laboratoire de virologie, CHU Dupuytren, 87042, Limoges, France. sylvie.rogez@unilim.frThe infection by the hepatitis viruses, when appearing during the pregnancy, could result indamages for the infant. However, risks differ according to the implicated virus. Hepatitis B virusinfection, for which prevalence varies according to areas, is injurious when the mother is chronicHBsAg carrier. Risk consists of neonate's contamination during the labour, and if contaminated,the neonate becomes a chronic carrier himself in 80 to 90% of cases. When the mother is positivefor viral DNA in her serum, transmission rate is estimated at 90%. In the opposite, if the mother isnegative for viral DNA in the serum, transmission rate is about 10 to 30%. HBsAg screening isobligatory in France during the sixth month of pregnancy: in case of positivity, serovaccination ofthe neonate is systematically carried out. Protection rate is 100% if the mother had a low viral load(< 150 pg/ml) at the end of pregnancy, and weaker (about 70%) if the mother had a higher level ofviral DNA.Transmission risk of hepatitis C virus (HCV) is much lesser, since it is about 5% for awoman who is positive for viral RNA at the end of her pregnancy, and at least 10% if the womanis moreover positive for the HIV. Risk is more important if the woman had an important plasmaticviral load (> 10 5 copies/ml) and if the duration between membrane rupture and delivery is long.Vaginal delivery and breast-feeding are not advised. Neonates from mothers who replicate theHCV at the end of pregnancy are serologically evaluated until 12-15 months of age, in order todetermine their possible contamination.Delta virus transmission from mother to infant isexceptional and could be avoided by the HBV serovaccination of the new-born.Intra-uterotransmission of hepatitis A virus is very rare, but perinatal transmission could occur. Materno-fetaltransmission of hepatitis E virus has been reported, but the virus is essentially dangerous for themother, resulting in a mortality rate of 15 to 25% if the acute infection occurs during the thirdtrimester of the pregnancy.Ranger-Rogez S, Denis F. Hepatitis B mother-to-child transmission. Expert Rev Anti-infectiveTher 2004; 2:133-145.Laboratoire de Virologie, CHU Dupuytren, 2 Avenue Martin Luther King, 87042 Limoges Cedex,France. sylvie.rogez@unilim.frApproximately 350 million people are estimated to be chronically infected with hepatitis B virus,leading to an important public health problem. In highly endemic areas where 8 to 15% of peopleare chronically infected with hepatitis B virus, the risk for the neonate to be perinatally infected bythe chronically infected mother, then to become chronically infected themselves, is very high. Inthose countries, the World Health Organization recommends hepatitis B vaccination systematicallyat birth, independent of hepatitis B virus maternal status. This vaccination program has begun toinduce a rapid decrease in the number of acute hepatitis B virus infections and has also had asecondary effect of a decrease in related sequels. Lamivudine (Zeffix, GlaxoSmithKline), whenassociated with the immunization of the neonate, was recently demonstrated to dramatically reducethe residual risk of perinatal transmission. In intermediate and low endemicity areas, a systematichepatitis B surface antigen screening is recommended during pregnancy, allowing, in the case ofpositivity, a selective hepatitis B virus neonate immunization during the first 12 h of life. HepatitisB virus vaccination of children born to hepatitis B surface antigen-positive mothers confers longtermimmunity.35